Mechanism for re-setting to zero the digit rolls of impulse counters



May 5, 1964 H. KREBSDZIQ 3,

MECHANISM FOR RE-SETTING TO ZERO THE DIGIT ROLLS OF IMPULSE COUNTERS Filed Aug. 50, 1961 Z/UAST KRKBSDZ/O lyr'dozbmc 1 ATTOEIVZYS 3,131,861 MECHANHSM FOR RE SETTWG T ZERO THE DIGIT ROLLS 0F IMPULSE COUNTERS Horst Krehsdzio, Peine, Hannover, Germany, assignor t0 Elmeg Eiektro-Mecanik G.m.b.H., Peine, Hannover, Germany i z Filled Aug. 30,1961, Ser. No. 135,013 Claims priority, application Germany Sept. 2,1960 9 Claims. (Cl. 235-144) I The invention relates to a mechanism for resetting to zero the digit rolls of impulsecounters provided with United States Patent 0 restoring springs which act on the drive means for the digit rolls.

The restoring springs. of such impulse counters exert a detrimentalefiect e.g. in that they press the driving pawl, Graham lever or the like rather tightly against the driving mechanism connected to the first digit roll and thus create friction forces which are even intensified in the operation of the counter because of the unavoidably present grit. When returning the digit rolls'to the starting position, these undesirable friction forces can cause considerable. difficulties. These difficulties are intensified by the fact that said friction forces become effective via various levers which materially increases the power requirement for returning the digit rolls to the starting position.

In order to avoid these difiiculties, it has already been proposed to divide the driven digit roll transversely to its axis and to connect the two parts by a pinion which, together with the decimal transmission pinions, is disengaged prior to the start of the return movement by the return lever. By this measure the driving means need not follow the return movement; only the digit rolls are then movedito the starting position. This known pro= posal is, however, relatively costly and quite considerably increases the costs of production of such an impulse counter. l

The invention has the. object of avoiding these disadvantages and of finding a simpler solution to the present problem.

Thus according to the present invention there is provided a. mechanism for resetting the digit rolls to zero including a return member movable to reset the rolls to zero and means whereby movement of said member to reset said rolls serves to render said restoring spring ineffective. so that while said rolls are being resetto Zero said spring does not act on said drive means.

As compared to the known proposal, this solution is more economical and has the further advantage of not requiring thesame amount of space which, in general, is

not available on account of restricted space conditions.

Thus, eg the German Federal Posts,;a main user of such impulse counters, have specified for counters having certain features a certain width of construction which results from other necessities which need not'be mentioned here. This width of construction can, in general, not be adhered to with the above-mentioned known proposal, while it causes no difiiculties whatever to adhere to it if impulse 3,131,861 Patented May 5., 1964' this faulty positioning, it is preferred to provide, additionally to the restoring spring, a second much weaker spring which acts in the same sense as the restoring spring even during the return movement of the digit rolls to their starting positions. The restoring spring thus generates a relatively strong force when acting, while the additionally provided spring exerts a relatively small force continuously. The friction forces provoked by the additional springare insufficient to give rise to the difficulties men tioned above.

The invention is diagrammatically illustrated by way of example by reference to two embodiments.

In the drawings:

FIG. 1 is a side view of the relevant parts of an impulse counter constructed according to the invention with a zero resetting mechanism for the digit rolls, known parts of the counter which are irrelevant for the invention not being shown, and

FIG. 2 shows a part of the embodiment of FIG. 1, in the position in which the restoring spring is disabled;

FIG. 3 is a view similar to H6. 2 of a second embodiment having an additional spring.

The drivable digit roll )1, with its single circular disc, shown in FIG. 1 has driving pins 2, with which pawl means such as a Graham lever 3 engages. .The hinged armature of a driving magnet (not shown) is denoted by4. Lever 3 is pivotably mounted upon a pivot axis 20 and is provided with a cut-out portion 22 receiving a pin 24 which is connected to a lever 13. Lever 13 is suitably connected to armature 4 and is pivotably mounted upon a pivot pin 17. With no current flowing in the coil of its associatedmagnet, this armature 4 is pressed back into its starting position by a restoring spring 5. The restoring spring 5 is provided with an arm 5 engaging an abutment 14 and with an arm 6 whose free end rests upon an inclined surface 7 of a return lever 8 movement of the digit rolls, the restoring spring 5 is lifted off" the armature 4. The contact pressure of the Graham lever on the driving pins 2 is thus discontinued, and friction forces are therefore eliminated. It is not absolutely necessary that the arm 6 of the restoringspring 5 should in the starting position of the clearance mov e ment of lever 8 rest on the slant surface 7 thereof. It can be advantageous to have this contact only effected when the clearance lever has covered a certain distance which, in general, should be kept small. 1

When the clearance lever 8 has been actuated, the restoring spring 5 no longer influences the armature 4 (FIG. 2).

FIG. 3 shows a second embodiment by way of example, in which instead of only one restoring spring 5, two springs 9 and 10 are provided, the arm 11 being associated with spring 9 and arm 12 with spring 10. The spring 10 exerts a relatively low force upon a lever 13 fixedly connected to the armature 4, while the spring 9 exerts a strong force upon this lever. Upon actuating the return lever 8, onlythe spring 9 is lifted off as shown in FIG. 3. Theembodiment of FIG. 1 need only be modified by providing, in addition to the abutment 14 of the restoring spring 9, two abutments 15 and 16 for the arms of the additional spring 10. The abutments 14 and 15 are fixedly mounted on the housing of the counter; the abutment 16 is provided on thelever 13. In this case both springs surround a pivot pin17 which is mounted in the housing of the counter in a suitable manner. The additional spring in acts, with a much weaker force, in the same direction as the restoring spring 9 even during the return movement of the digit roll to prevent the digit roll, after reaching the starting position, from coming into engagement in a position that would cause a displacement of the digit roll prior to the next actuation thereof.

Although as described the restoring spring is disabled directly by the return member other arrangements are possible. For example, the restoring spring could be disabled indirectly by the part of the drive means on which it normally acts.

My present invention may be advantageously incorporated into an impulse counter of the type shown in my DBP 1,104,745, and the complete resetting mechanism utilized according to the present invention may include a cardioid concentric with the shaft of digit roll 1 and engageable during the zeroing procedure by a return lever of the type shown in my aforementioned German patent application.

I claim:

1. An impulse counter comprising a digit roll, drive means for said digit roll including'oscillatable pawl means positively actuated in one direction and spring restored in the opposite direction to effect a one-step advance of the digit roll, a restoring spring normally operatively engaging said'drive means, and means for resetting said digit roll to zero, said last mentioned means including means operatively connecting said resetting means with said restoring spring to effect disengagement of said restoring spring from said drive means and therewith to render said restoring spring ineffective during the resetting movement of said digit roll to zero so as to permit said pawl means to oscillate substantially without interference by said restoring spring during resetting of said digit roll.

2. An impulse counter comprising a digit roll, drive means for said digit roll including oscillatable pawl means positively actuated in one direction and spring restored in the opposite direction to effect a one step advance of the digit roll, a restoring spring normally operatively engaging said drive means, and means for resetting said digit roll to zero, said last mentioned means including manually operable lever means having an end portion thereof directly engaging said restoring spring during the zero-setting operation to substantially completely disengage said restoring spring from said drive means and therewith to render said restoring spring ineffective during the zero-setting operation so as to permit said pawl means to oscillate substantially without interference by said restoring spring during resetting of said digit roll.

3. An impulse counter comprising a digit roll, drive means for said digit roll including a bifurcated oscillating pawl, a restoring spring normally operatively engaging said drive means, an additional spring operatively engaging said drive means in the same sense as said'restoring spring, said additional spring being considerably weaker than said restoring spring, said drive means being positively actuated in one direction and being springrestored by said restoring spring in the opposite direction to effect a one-step advance of the digit roll and'means for resetting said digit roll to zero, said last mentioned means including means engaging said restoring spring to render said restoring spring ineffective during movement of said digit roll to zero.

4. An impulse counter as defined in claim 3, wherein said restoring spring and said additional spring are mounted essentially coaxially.

5. An impulse counter including a digit roll, drive means for said digit roll providing a positive actuation of said drive means in one direction and enabling spring restoration in the opposite direction to effect a one-step advance of the digit roll including an armature having a starting position and oscillatable bifurcated lever means operatively connecting said armature and said digit roll, a restoring spring normally engaging one of the two parts consisting of said armature and lever means and effective to return said armature to its starting position, and means for resetting said digit roll to zero, said last mentioned and therewith to render said restoring spring ineffective during movement of said digit roll to zero.

6. An impulse counter including a digit roll, drive means for said digit roll including an armature having a starting position and oscillatable bifurcated lever means forsaid digit roll to provide a positive actuation of said drive means in one direction and enable spring restoration in the opposite direction, to thereby effect a one-step advance of the digit roll, a restoring spring normally effective to return said'armature to its starting position, an additional spring operatively engaging said drive means in the same sense assaid restoring spring, said additional spring being considerably Weaker than said restoring spring, and means for resetting said digit roll to zero, said last mentioned means including means engaging said restoring spring to render said restoring spring ineffective during movement of said digit roll to zero and therewith enable oscillation of the lever means during the resetting operation substantially without interference by said restoring spring.

7. In an impulse counter having a digit roll means, pins spaced around the periphery of said digit roll means, pawl means engaging said pins to provide a positive actuation of said drive means in one direction and enabling spring restoration in the opposite direction, to thereby effect a one-step advance of said digit roll means, a pivotably mounted armature having a starting position and operatively connected to said pawl means, a restoring spring having an arm portion thereof engaging said armature and normally urging said armature into a starting position, and means for resetting said digit roll means to zero including means directly engaging said restoring spring to substantially completely disengage said restoring spring from said armature and therewith to render said restoring spring ineffective during movement of said digit roll means to zerowhereby said bifurcated oscillatable lever means is able to oscillate during the resetting operation substantially without interference by said restoring spring.

8. A resetting mechanismfor impulse counters having a digit roll with a start position, an actuating mechanism provided with an actuating member and with a bifurcated oscillating pawl positively actuated in one direction and 7 spring restored in the opposite direction, to effect a onestep advance of the digit roll, a restoring spring normally operatively connected with said actuating mechanism to provide the said spring restoring thereof in the said opposite direction, and resetting means for resetting said digit roll to zero, the improvement essentially consisting of means operatively connecting said resetting means with said restoring spring for completely disengaging said restoring spring from the actuating member of the actuating mechanism upon actuation of said resetting means prior to return of the digit roll into the start position thereof.

9. A resetting mechanism according to claim 8, further comprising an additional return spring of lesser spring force than the first-mentioned restoring spring and operable on the actuating mechanism in the same direction as said restoring spring, said additional spring being oper able on said actuating mechanism during the return of the digit roll to the start position thereof;

References Cited in the file of this patent UNITED STATES PATENTS 755,695 Pidgin Mar. 29, 1904 910,806 Falvey Jan. 26, 1909 1,678,762 Beskow July 31, 1928 2,150,666 Webb Mar. 14, 1939 

1. AN IMPULSE COUNTER COMPRISING A DIGIT ROLL, DRIVE MEANS FOR SAID DIGIT ROLL INCLUDING OSCILLATABLE PAWL MEANS POSITIVELY ACTUATED IN ONE DIRECTION AND SPRING RESTORED IN THE OPPOSITE DIRECTION TO EFFECT A ONE-STEP ADVANCE OF THE DIGIT ROLL, A RESTORING SPRING NORMALLY OPERATIVELY ENGAGING SAID DRIVE MEANS, AND MEANS FOR RESETTING SAID DIGIT ROLL TO ZERO, SAID LAST MENTIONED MEANS INCLUDING MEANS OPERATIVELY CONNECTING SAID RESETTING MEANS WITH SAID RESTORING SPRING TO EFFECT DISENGAGEMENT OF SAID RESTORING SPRING TO EFFECT DISENGAGEMENT OF SAID RESTORING SPRING FROM SAID DRIVE MEANS AND THEREWITH TO RENDER SAID RESTORING SPRING INEFFECTIVE DURING THE RESETTING MOVEMENT OF SAID DIGIT ROLL TO ZERO SO AS TO PERMIT SAID PAWL MEANS TO OSCILLATE SUBSTANTIALLY WITHOUT INTERFERENCE BY SAID RESTORING SPRING DURING RESETTING OF SAID DIGIT ROLL. 